Through transom mounted drive unit for watercraft



May 14, 1968 E. c. KIEKHAEFER 3,382,839

THROUGH TRANSOM MOUNTED DRIVE UNIT FOR WATERCRAFT FiledFeb. 16, 1965 5Sheets-Sheet 1 INVENTOR ELMER CARL KIEKHAEFER qndrus StarlQ THROUGHTRANSOM MOUNTED DRIVE UNIT FOR WATERCRAFT Filed Feb. 16, 1965 5Sheets-Sheet 2 INVENTOR.

6 ELMER CARL KIEKHAEFER 4 BY (7 22 j ndrus Star/Q AffonwEYS M y 1968 E.c. KIEKHAEFER 3,382,839

THROUGH TRANSOM MOUNTED DRIVE UNIT FOR WATERCRAFT Filed Feb. 16, 1965 5Sheets-Sheet 3 ELMER CARL KIEKHAEFER ndrus StarKg Arrow/ears May 14,1968 E. c. KIEKHAEFER 3,382,339

THROUGH TRANSOM MOUNTED DRIVE UNIT FOR WATERCRAFT Filed Feb. 16, 1965 5Sheets-Sheet 4 I INVENTOR. Ewen CARL KIEKHAEFER BY 71ndrus Star/(g y 14,1958 E. c. KIEKHAEFER 3,382,839

THROUGH TRANSOM MOUNTED DRIVE UNIT FOR WATERCRAFT Filed Feb. 16, 1965 5Sheets-Sheet 5 I ln aw i if, 9

INVENTOR. ELMER CARL KIEKHAEFER 71ndr'us Star/Q Affomvsvs United StatesPatent 3,382,839 THROUGH TRANSOM MOUNTED DRIVE. UNIT FOR WATERCRAFTElmer Carl Kiekhaefer, Winter Haven, Fla., assignor to BrunswickCorporation, Chicago, 111., a corporation of Delaware Filed Feb. 16,1965, Ser. No. 433,089 9 Claims. (Cl. 115-41) ABSTRACT OF THE DISCLOSUREA drive unit in which the engine is rigidly connected through an openingin the transom of a boat to the propeller unit. The drive unit ispivoted on horizontal trunnions for tilting movement and is rotatablysupported by an intermediate member for steering, Adjustable abutmentmeans between the drive unit and the transom establishes the trim of theboat.

This invention relates generally to marine propulsion drive means andmore particularly to a through transom mounted drive unit.

It is generally an object of this invention to provide a through transomsuspension for a drive unit providing for steering movement of the unitin a generally horizontal plane about a generally vertical axis and fortilt movement in a generally vertical plane about a generally transversehorizontal axis.

Briefly, the invention contemplates a drive unit which extends throughan Opening in the transom and has a power source disposed inboard of thewatercraft and a propeller unit disposed outboard. The suspensionproviding for steering and tilt movement of the drive unit includes auniversal bearing assembly interposed between the unit and the transom.

Generally, according to one aspect of the invention, the drive unitincludes a cylindrical drive shaft housing which is rotatably mountedwithin a generally vertically disposed sleeve to provide for steeringmovement of the unit. The sleeve in turn is formed integrally with atrunnion structure including opposed trunnions extending normal to thesleeve. Transom support means aligned with an opening in the transom ofthe watercraft forms a transversely extending bearing assembly adaptedto journally receive the opposed trunnions and provide for tilt movementof the drive unit. Adjustable abutment means are interposed between thedrive unit and the transom to establish the operating trim of the unit.

The drawings furnished herewith illustrate the best mode for carryingout the invention as presently contemplated and set forth hereinafter.

In the drawings:

FIGURE 1 is an elevational view with the watercraft broken away andsectioned to show the drive unit mounting of this invention;

FIG. 2 is an enlarged partial elevational view partially in section ofthe drive unit mounting;

FIG. 3 is an enlarged perspective view taken generally on line 3-3 ofFIG. 2 and with parts broken away and sectioned;

FIG. 4 is a view taken generally on line 4-4 of FIG. 2;

FIG. 5 is an enlarged view taken generally on line 55 of FIG. 2;

FIG. 6 is an enlarged view taken generally on line 66 of FIG. 5 showingthe reverse latch hook in engagement with the tilt adjustment rod forreverse drive operation of the unit and in phantom lines showing thelatch 3,382,839 Patented May 14, 1968 hook disengaged from the tiltadjustment rod as for forward drive operation of the unit;

FIG. 7 is a view generally similar to FIG. 6 and shows the adjustingmeans for the tilt adjustment rod with the latter in one of its extremepositions and in phantom shows the rod in its other extreme position;

FIG. 8 is an elevational view with parts broken away and sectioned andshows another embodiment of the invention;

FIG. 9 is an elevational view with parts broken away and sectioned andshows still another embodiment of the invention; and

FIG. 10 is a sectional view taken generally on line 1(l10 of FIG. 9.

Referring to the drawings, the through transom mounted drive unitincludes a drive shaft housing 1 which extends through the opening 2 inthe transom 3 of the partially shown watercraft 4. The drive shafthous-' ing 1 carries a power source or engine 5 at the upper inboard endthereof and a propeller unit 6 at the lower outboard end thereof.

The propeller 7 is carried on a generally horizontal propeller shaft,not shown, which is selectively rotatable in opposed directions torotate the propeller correspondingly and thereby provide for forward andreverse propulsion of the watercraft. Suitable gearing, not shown,drivingly connect the propeller shaft to the drive shaft 8 which extendsthrough the drive shaft housing 1 and is in turn drivingly connected tothe shaft 9 of engine 5.

The exhaust products from engine combustion are conducted in the usualmanner from engine 5 through the generally hollow drive shaft housing 1to the propeller unit 6 for discharge under water through the dischargeopening 10 rearwardly of the propeller. The cooling water for engine '5is picked up through the inlets 11 in the lower unit 6 and is conductedto the engine through conduit 12 extending generally vertically withinthe drive shaft housing.

The through transom drive unit is universally mounted within the transomopening 2 to provide for tilt movement of the unit in a generallyvertical plane about a generally transverse horizontal axis and steeringmovement in a generally horizontal plane about a generally verticalaxis.

The mounting or suspension for the drive unit includes the intermediatemember 13 provided with a stepped generally vertically extendingcylindrical bore 14 which con stitutes a swivel bearing and is adaptedto rotatably receive the cylindrical portion 15 of the drive shafthousing 1 to provide for steering movement of the drive unit within theintermediate member. The intermediate member 13 extends between theupper and lower radially extending annular flanges 16 and 17,respectively, on drive shaft housing 1 and a pair of thrust washers 18and 19 are disposed between the respective flanges and the correspondingends of the intermediate member.

The intermediate member 13 includes the transversely extendingcylindrical portion 20 which extends generally equidistantly to eitherside of the drive shaft housing portion 15, and aligned trunnions 21 areprovided on the ends thereof. The trunnions 2l1 are disposed in thetransversely spaced and aligned bearings 22 on the tilt axis torotatably support the drive unit and provide for tilt movement of theunit in a generally vertical plane.

The intermediate member 13 along with the drive unit are supportedwithin a plate assembly v23 comprising complementary opposed upper andlower plate members 24 and 2'5 which are secured together by -aplurality of bolts 26'.

Lower plate member of plate assembly 23 includes the peripheral flangeportion 27 adapted to engage with the outboard side of transom 3adjacent to the opening 2. A transom plate member 28 having aconfiguration corresponding generally to that of flange portion 27 ofplate member is disposed inboard of the watercraft 4 adjacent to opening2 and a plurality of bolts 29 secure the plate members 25 and 23together to sandwich the transom 3 therebetween and rigidly mount theplate member 25 in place.

Intermediate the flange portion 27 the plate member 2-5 includes aninwardly projecting portion 30 which extends through the transom opening2 and terminates with a generally rectangular parting surface 31 in atransverse plane disposed angularly relative to the generally verticaltransom 3. From parting surface 31, a transversely extendingsemi-cylindrical cavity 32 is formed in portion 30 of plate member 25and is adapted to receive the cylindrical portion 20 of the intermediatemember 13. The trunnions 21 on member 13 are rotatably disposed in thetransversely spaced and aligned semi-cylindrical cavities 8-3 providedin the transversely spaced walls of plate member portion 30 to form thelower portions of bearings 22. In assembled relation, the lower portionof the intermediate member 13 along with the drive unit extend outboardthrough the opening 34 of plate member por tion 30 and between thespaced outboard strengthening ribs 35 extending rearwardly from platemember 25. The opening 34 is oval in shape being elongated in thevertical plane containing the drive shaft axis to permit trim adjustmentof the drive unit and accommodate tilt movement of the unit. A generallyannular flexible beltion for the tilt and swivel bearings against waterand and other foreign matter.

The upper cover plate member 24, of the plate assembly 23 includes thetransversely spaced and aligned semicylindrical bearing cavities 37 andintermediate semicylindrical cavity 38 which respectively complement thecavities 33 and 32 of plate member 25 to rotatably confine theintermediate member 13 in the assembled relation of the plate members.The parting surface 39 on cover plate member 24 engages with thecomplementary surface 3 1 on plate member 25 to receive the bolts 26 forassembly. In assembled relation, the upper portion of the intermediatemember 13 along with the drive unit extend inboard through the platemember oval-shaped opening 40 opposite from opening 34 in plate member25 to provide for trim adjustment and tilt movements.

For a relatively common 12 transom angle relative to the vertical, thethrough transom mounting of necessity requires the drive unit to beinclined at a substantial forward rake which is desirable for itsWeedless characteristics and for ease of tilting upon striking submergedor floating objects. The trim or rake angle of the drive unit isestablished by engagement between the pair of transversely spaced arms41 associated with the drive unit and the tilt adjustment rod orabutment means 42 associated with the transom 3 as will be furtherdescribed hereinafter.

The arms 41 disposed on opposite sides of the drive unit are providedwith inwardly facing transverse recess openings 43 at the lower endsthereof which complement and engage the tapered hexagonal transverseextensions 44 on the intermediate member trunnions 21 outwardly ofbearings 22 to rotationally lock the arms relative to the drive unit.The arms 41 are further secured against axial displacement relative tothe extensions 44 by the threaded members 45 which extend through thearms and thread into the corresponding trunnion extensions. Thus, thearms 41 at all times move correspondingly with the drive unit about thetilt axis.

During forward drive operation of the unit each arm 41 is biasedrearwardly by the propeller thrust to normally maintain the notch 46 inthe arm in abutting engagement with the tilt adjustment rod 42 tothereby establish the operating trim of the drive unit. However, uponstriking a submerged or floating object, the drive unit is free to pivotrear-wardly to clear the object from beneath the unit.

The momentum imparted to the drive unit upon striking an object is atleast in part cushioned by contraction of the normally extended shockabsorbers 4 7 having one end thereof pivotally secured to thecorresponding movable arms 41 and the other end thereof pivotallysecured to the rod 4-8 carried by the inwardly extending projections 49on fixed plate member 25. The shock absorbers -47 may further serve tolimit the angular tilt movement of the drive unit. The compressionsprings 50 surround the shock absorbers 47 and have their opposed endsdisposed in the spaced cups 51 and 52 respectively carried by therelatively movable parts of the shock absorbers. The springs 56 serve toagain extend the contracted shock absorbers 47 to thereby prevent asticking of the drive unit in the fully tilted position and assureimmediate return of the unit to the operating trim position.

During reverse drive operation of the drive unit, the arms 41 along withthe drive unit are locked relative to the tilt adjustment rod 42 asgenerally shown in FIGS. 5 and 6 to prevent the reverse thrust of thepropeller 7 from merely moving the unit angularly about its tilt axisand out of the water. The locking is effected by a reverse latch hook 53pivotally mounted on arms 41 and adapted to engage on the opposite sideof rod 42 from the abutting engagement of arms 41 to secure the rodtherebetween. Hooks 53 are biased to the rod engaged position by thetension springs '54 disposed between the respective hooks and thecorresponding arms 41.

During forward drive operation of the drive unit, the latch hooks 53 aremoved to and maintained in a disengaged position from rod 42 against thebias of springs 54 by the actuating rod 55 which engages with inwardlyextending projections 56 on the hooks and extends rearwardly around thedrive unit and is pivotally supported by the spaced arms 41. A pivotablelever 57 mounted on the drive unit and operatively connected to thedrive unit control means, not shown, is adapted to move the actuatingrod 55 to the hook disengaged position and to maintain the rod in thatposition during forward drive operation of the drive unit. Duringreverse drive operation of the drive unit, lever 57 is pivoted to aninoperative position to allow springs 54 to effect and maintainengagement of the reverse hooks 53.

Provision is made for varying the operating trim or rake angle of thedrive unit within a given range as provided by adjusting movements ofthe tilt adjustment rod 42. The rod 42 extends around the rearwardportion of the drive unit and the opposed transversely extending endportions thereof extend through the trans versely spaced and alignedarcuate cam slots 58 in the corresponding stationary cam brackets 59provided on the upper cover plate 24. The slots 58 are struck on an arefrom the tilt axis of the drive unit so that regardless of the positionof the rod 42 within the slots, engagement of the rod by the notches 46in the respective arms 41 is assured.

The transversely spaced stationary cam brackets 59 are provided withaxially aligned openings in spaced relation from the slots 58 forsupport of an axially and pivotally movable through rod 60 one end ofwhich is threaded to receive a tightening knob 61. Outwardly from thecam brackets 59, the through rod 60 carries corresponding adjusting cams62. The adjusting cam 62 on the end of rod 60 oppositely from the knob61 is fixedly secured to the rod while the adjusting cam adjacent to theknob is confined against pivotal movement relative to the rod but ismovable axially thereon by virtue of the engagement of the pin 63 in thecam with the slot 64 in the rod. Thus, the through rod and the adjustingcams 62 rotate together as a unit.

The transversely spaced adjusting cams 62 are provided with aligned camslots is spaced relation from the through rod 60 and formed on anincreasing radius from the axis of the through rod and in intersectingrelation with the cam slots 58 in the adjacent cam brackets 59. Thetransverse end portions of the tilt adjustment rod-42 extend through thecam slots 65 and, outwardly of the adjusting cams 62, form the abutmentsfor engagement by notches 46 on corresponding arms 41. For a giyenposition of the tilt adjustment rod 42, the knob 61 is threaded tightlyonto the rod 60 to draw the radial teeth 66 and 67 on the annular facingsurfaces of the adjustment earns 62 and the corresponding cam brackets59 respectively into meshing engagement to thereby secure the rod 42 in'the given position as determined by the intersecting cam slots 58 and65.

If it is desired to change the position of the tilt adjustment rod 42 tothereby alter the operating trim of the drive unit, the knob 61 isloosened upon the rod 60 permitting limited axial movement of rod 60 andadjusting cams 62 relative to the stationary cam brackets 59 to free theadjusting cams for pivotal movement relative to the cam brackets. Afterthe adjusting cams 61 have been freed to rotate relative to the cambrackets 59, the tilt adjustment rod 42 is free to move to any desiredposition within the cam slots 58 of the cam brackets as determined bythe intersecting cam slots 65 with corresponding rotation of theadjusting cams. With the tilt adjustment rod 42 relocated as desired inslots 58 of cam brackets 59, knob 61 is again tightened onto rod 60 tolock the adjusting cams 62 relative to the corresponding cam brackets tothereby secure rod 42 between the intersecting cam slots 65 and 58.

According to the embodiment of FIG. 8, the drive unit is universallymounted on the transom 3 of watercraft 4 by means of a spherical or ballassembly. The drive unit includes a drive shaft housing 68 which extendsthrough an opening 2 in the transom 3 and carries a power source in theform of an engine enclosed within cowl 69. at the upper inboard endthereof and a propeller unit 70 at the lower outboard end thereof. Thedrive shaft housing 68 comprises upper and lower housing portions 71 and72 respectively. The lower end of the upper housing portion 71terminates with a semi-spherical enlargement 73 which complements thesemi-spherical enlargement 74 on the upper end of the lower housingportion 72. The semi-spherical enlargements 73 and 74 of housingportions 71 and 72 respectively are joined on a transverse plane at -75by means of recessed bolts 76 to provide the drive shaft housing 68 witha spherical or ball enlargement 77.

The spherical or ball enlargement 77 of the drive unit is rotatalymounted within a complementary spherical or ball transom housingassembly or socket 78 comprising inner and outer transom plates 79 and80 respectively secured together by a plurality of bolts 81. The driveunit is rotatable about the axis of the drive shaft 82 for steering andis tiltable about a transom axis through the center of the sphericalassembly in a generally vertical plane as provided for by opposedopenings 83 and 84 in plates 79 and 89 respectively.

Referring to the embodiment of FIGS. 9 and 10, the drive unit issupported in the opening 2 of the transom 3 by means of the transomplate assembly 85 which defines a spherical or ball housing andcomprises inner and outer transom plates 86 and 87 secured together by aplurality of bolts 88 or the like. Oppositely from transorn 3 the innertransom plate 86 includes a hollow cylindrical portion 89 whichterminates with the outwardly extending annular flange 90. An engineenclosed within cowl 91 is rotatably mounted on the end of cylindricaltransom plate portion 89 and is confined against axial displacement bythe annular clamp ring 92 secured to the engine cowl 91 and projectingbeneath flange 90.

The drive shaft housing 93 extends downwardly through an opening 94 inthe outer transom plate 87 and carries a propeller unit 95 at the lowerend thereof and terminates with a ball housing portion 96 at the upperend thereof adapted to be rotatably supported within the spherical orball housing of the transom plate assembly 85. The drive shaft housing93 along with propeller unit 95 are adapted for tilt movement in agenerally vertical plane relative to the transom plate assembly 85 andthe cowl enclosed inboard engine as provided for in the transom plateopening 94.

To accommodate tilt movements of the outboard portion of the drive unitrelative to the inboard engine, the drive shaft 97 extends downwardlyfrom the engine through a longitudinally extending clearance slot 98 inthe rotatable ball housing portion 96 of drive shaft housing 93 and aflexible link 99 is interposed in the drive shaft at the tilt axiswithin the housing portion 96 to provide for a bending in the driveshaft as occasioned by tilt movements of housing 93. The engine enclosedwithin cowl 91 is interlocked to the ball housing portion 96 of thedrive shaft housing 93 by engagement of the keys 100 projectingdownwardly from the base portion of the engine cowl 91 in transverselyspaced relation and on either side of drive shaft 97 within thelongitudinally extending keyways or slots 101 in housing portion 96. Theinterlock as provided by engagement of keys 1% within correspondingslots 101 provides for steering of the drive unit by rotation of thecowl enclosed inboard engine relative to the transom plate assembly 85and is adapted to accommodate the tilt movements of the outboard portionof the drive unit relative to the engine.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim:

1. In combination with a watercraft having a transom and an opening inthe transom, a drive unit disposed in the transom opening and includinga drive shaft housing carrying a power source at the upper end thereofand a propeller unit at the lower end thereof, an outer transom platemember having a peripheral portion adapted to engage the out-board sideof the transom and an intermediate portion aligned with and projectinginwardly through the transom opening, an inner transom plate memberenga-geable with the inboard side of the transom and generallycomplementing the peripheral portion of the outer transom plate member,means securing the inner and outer transom plate members together tosandwich the transom there/between, a complementary cover plate membersecured to the intermediate portion of the outer transom plate member,said cover plate member and the intermediate portion of the outertransom plate member forming a transverse horizontal cylindrical boretherebetween and respectively having generally vertically alignedopenings communicating with said bore, and an intermediate membercomprising a pair of intersecting cylinders, one of said cylinders beingdisposed generally vertically and being adapted to rotatably carry acylindrical portion of the drive unit drive shaft housing to provide forsteering movement of the drive unit about a generally vertical axis, andthe other of said cylinders being disposed transverse to the drive unitand rotatably within the bore formed between the cover plate member andthe intermediate portion of the outer transom plate member with thedrive unit extending through the generally vertically aligned openingscommunicating with the bore, said cover plate member and outer transomplate member supporting the drive unit for pivotal tilting movementabout a transverse horizontal axis with the power source disposedinboard of the watercraft and the propeller unit disposed outboard.

2. In combination with a watercraft having a transom and an opening inthe transom, a drive unit including a power source and propeller unitrigidly connected together through said transom opening, a plate memberhaving a peripheral portion adapted for securement to the transom of thewatercraft and an intermediate portion aligned with the transom opening,a cover plate member complementing the intermediate portion of saidfirst named plate member and secured thereto to form a support assembly,and an intermediate member interposed between the support assembly andthe drive unit and rotatably carried by said support assembly betweenthe cover plate member and the intermediate portion of said first namedplate member, said intermediate member supporting the drive unit forpivotal steering movement about a generally vertical axis and beingsupported by the support assembly for pivotal tilting movement about atransverse horizontal axis with the power source disposed inboard of thewatercraft and the propeller unit disposed outboard.

3. In combination with a Watercraft having a transom and an opening inthe transom, a drive unit including a power source and propeller unitrigidly connected together through said transom opening, a lower platemember having a peripheral portion adapted to engage the outboard sideof the transom and an intermediate portion aligned with and projectinginwardly through the transom opening, an upper and lower plate memberengageable with the inboard side of the transom and generallycomplementing the peripheral portion of the lower plate member, meanssecuring the upper and lower plate members together to sandwich thetransom therebetween, a cover plate complementing the intermediateportion of the lower plate member and secured thereto to form a supportassembly, and an intermediate member interposed between the supportassembly and the drive unit and rotatably carried by said supportassembly between the cover plate member and the intermediate portion ofsaid first named plate member, said intermediate member supporting thedrive unit for pivotal steering movement about a generally vertical axisand being supported by the support assembly for pivotal tilting movementabout a transverse horizontal axis with the power source disposedinboard of the watercraft and the propeller unit disposed outboard. V

4. In combination with a watercraft having a transom and an opening inthe transom, a drive unit including a power source and a propeller unitrigidly connected together through said transom opening, support meansrigidly secured to the transom of the watercraft and including a platemember extending peripherally of the transom opening, an intermediatemember interposed between the support means and the drive unit, saidintermediate member supporting the drive unit for pivotal steeringmovement about a generally vertical axis and being supported by thesupport means for pivotal tilting movement about a transverse horizontalaxis with the power source disposed inboard of the watercraft and thepropeller unit disposed outboard, abutment means associated with thetransom and being selectively movable within a cam slot struck on an arefrom the tilt axis of the drive unit, and arm means mounted on theintermediate member for rotation therewith about the tilt axis and beingengageable with the abutment means to establish the operating trim ofthe drive unit.

5. In combination with a watercraft having a transom and an opening inthe transom, a drive unit including a power source and a propeller unitand rigidly connected together through said transom opening, supportmeans rigidly secured to the transom of the watercraft and including aplate member extending peripherally of the transom opening, anintermediate member interposed between the support means and the driveunit, said intermediate member supporting the drive unit for pivotalsteering movement about a generally vertical axis and being supported bythe support means for pivotal tilting movement about a transversehorizontal axis with the power source disposed inboard of the watercraftand the propeller unit disposed outboard, abutment means associated withthe transom and being selectively movable within a fixed cam slot, meansfor moving the abutment means including means movable relative to thecam slot and adapted to carry the abutment means through a range ofadjustment, and means associated with the drive unit and engageable withthe abutment means to establish the operating trim of the unit.

6. The invention as set forth in claim 5 wherein the means for movingthe abutment means includes a rotatable cam member having an arcuate camslot at varying radius from the cam member axis, said cam slot beingmovable in intersecting relation relative to the fixed cam slot to carrythe abutment means through its range of adjustment.

'7. In combination with a watercraft having a transom and an opening inthe transom, a drive unit disposed in the transom opening and includinga power source rigidly connected through the transom opening to apropeller unit having a propeller selectively rotatable in opposeddirections to provide for forward and reverse propulsion of thewatercraft, support means rigidly secured to the transom of thewatercraft, an intermediate member interposed between the support meansand the drive unit, said intermediate member supporting the drive unitfor pivotal steering movement about a generally vertical axis and beingsupported by the support means for pivotal tilting movement about atransverse horizontal axis with the power source disposed inboard of thewatercraft and the propeller unit disposed outboard, abutment meansassociated with the transom, means associated with the drive unit andengageable with the abutment means to establish the operating trim ofthe unit, a latch hook on the drive unit and normally biased intoengagement with the abutment means to lock the drive unit relative tothe transom when the drive unit is operated to provide for reversepropulsion of the watercraft, and means engageable with the latch hookand adapted to move and maintain the latch hook out of engagement withthe abutment means when the drive unit is operated to provide forforward propulsion of the watercraft.

8. The invention as set forth in claim 7 wherein the drive unit meansengageable with the abutment means constitutes an arm carried by theintermediate member and the latch hook is carried by the arm, rod meanscarried by said arm and engageable with said latch hook, means normallybiasing the latch hook and rod means to a position of latch hookengagement with the abutment means and thereby providing for securementof the drive unit relative to the transom when the unit is operated forreverse propulsion of the watercraft, and means movably mounted on thedrive unit and engageable with said rod means to move and maintain therod means together with the latch hook out of the engaged position withthe abutment means when the drive unit is operated to provide forforward propulsion of the watercraft.

9. In marine propulsion drive means adapted for watercraft having atransom and an opening in the transom, a drive unit including a powersource and a propeller unit rigidly connected together through thetransom opening with the power source inboard of the watercraft and thepropeller unit outboard, a plate member having a peripheral portionadapted for securement to the transom of the watercraft and anintermediate portion for alignment with the transom opening, a coverplate member complementing the intermediate portion of the first namedplate member and secured thereto to form a support assembly, and anintermediate member interposed between the support assembly and thedrive unit, said intermediate member supporting the drive unit forpivotal steering movement about a generally vertical axis and beingsupported 9 by the support assembly for pivotal tilting movement about atransverse horizontal axis.

References Cited UNITED STATES PATENTS 3,158,346 11/1964 Jagger 115-41 X3,175,530 3/1965 Petterson 115-41 190,312 5/1877 Gray et a1. 11541Johnson et a1. 1l5--41 Griffith 11541 North 115-41 Urbassik 115-41MILTON BUCHLER, Primary Examiner.

T. MAJOR, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,382,839 May 14, 1968 Elmer Carl Kiekhaefer It is certified that errorappears in the above identified patent and that said Letters Patent arehereby corrected as shown below:

Column 7, line 28, cancel "and lower"; line 68, cancel "and", secondoccurrence.

Signed and sealed this 4th day of November 1969.

(SEAL) Attest:

Edward M. Fletcher, 11'.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR.

